Co-architect of Hagia Sophia, master geometer
A mathematician, geometer, and architect of the Byzantine Empire who, with Isidore, designed Hagia Sophia. He was himself one of the greatest mathematicians of his age, expert above all in geometry and mechanics — and it was this deep mathematical grounding that let them dare the unprecedented structural challenge of "setting a huge dome in the air over walls full of windows." After Hagia Sophia was built, its dome partly collapsed in an earthquake and was repaired, but the pendentive-dome structure it pioneered was borrowed again and again by the mosques of the Islamic world and the cathedrals of the Renaissance — here, mathematics became directly the most moving of spaces.
Anthemius was not a craftsman-architect in the traditional sense, but a top geometer. With the equally mathematical Isidore, he treated Hagia Sophia as a vast problem of geometry and mechanics to be solved. They dared to suspend the dome and open the load-bearing base full of windows precisely on the strength of exact structural calculation. This church proved that the greatest architecture is often also the most profound mathematics.
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